The present application relates to standby power systems. More particularly, the present application relates to a method and apparatus for charging and providing a standby power source for use in systems requiring an uninterruptible power supply.
Standby batteries are continuously charged at a constant voltage namely, a power supply to which they are connected. This constant charging allows the batteries to be fully charged for use in the event of a power outage. Standby batteries are necessary in a device requiring an uninterruptible power source in order to provide a standby or temporary source of power to the device and/or the system they are backing up.
The standby batteries are designed to provide a source of power for a particular device or system so that the system can be provided with an uninterrupted supply of power in the event of a failure of the first or main power supply. Standby batteries are of particular importance in applications where the system the batteries are connected to is required to provide an uninterrupted service. For example, cell phone towers, computer systems, apparatus and other systems for transfer of data through a medium wherein the data stream must be continuously provided and/or supported.
In order to provide a seamless transfer of power from the main power supply to the backup power supply these batteries are directly coupled to the main power supply and the electrical load. This direct connection serves two goals 1) to maintain the batteries at a full charge and 2) providing a seamless transfer from the main power supply to the backup power supply (e.g., uninterrupted power supply). In this configuration the batteries are maintained at a full charge by a direct connection with the main power supply. Accordingly, the batteries are constantly being charged regardless of whether the batteries are fully charged and do not require charging. The battery industry refers this condition as xe2x80x9coverchargexe2x80x9d. When the batteries are overcharged continuously, there are side reactions that reduce the batteries"" performance over time. The grids of the positive plates are corroded and the water in the electrolyte is decomposed into oxygen gas and hydrogen gas. Both of these reactions cause higher internal resistance in the battery, which reduces its performance.
Thus, as the internal resistance of the battery increases, it can no longer supply the same amount of energy at the same voltage. Since the side reactions are inevitable, the rate at which this change in resistance occurs is particularly important. This higher internal resistance is undesirable particularly in data transfer devices wherein the internal resistance is particularly important. This higher rate of resistance is undesirable particularly when the standby batteries are the sole source of power, for example, providing backup power to a system experiencing a power outage. Moreover, and in particular with regard to systems requiring an uninterrupted source of power (e.g., data transfer devices) change in internal resistance is particularly important.
A backup power supply, comprising: a storage medium for holding an electrical charge, the storage medium being adapted to be coupled to a DC bus by a switching device having an output end and an input end, the input end being coupled to a permanent power grid and the output end being configured to provide a source of power; a source of intermittent power coupled to the DC bus; and an operating system for determining whether the output end requires power from the storage medium, the operating system monitors the current of the source of intermittent power and if the current to the source of intermittent power exceeds a predetermined limit the operating system couples the storage medium to the DC bus by manipulating the position of the switching device, the operating system comprises a controller for determining which of a plurality of states the backup power supply should be in.
A backup power supply, comprising: a storage medium for holding an electrical charge being configured to be connected and disconnected from an electrical device; a source of intermittent power coupled to a power supply and the electrical device being configured to provide an amount power to the electrical device for a period of time long enough to connect the storage medium to the electrical device; and an operating system for determining whether the electrical device requires power from the storage medium. In one embodiment the operating system monitors the current of the source of intermittent power and if the current exceeds a predetermined limit the operating system couples the storage medium to the electrical device by manipulating the position of a switching device disposed between the electrical storage medium and the electrical device.
A control system for a backup power supply, comprising a control algorithm for continuously monitoring a plurality of states of the backup power supply having a plurality of capacitors, the plurality of capacitors being coupled to a power supply and an electrical load and a plurality of batteries being adapted to be coupled and uncoupled from the power supply and the electrical load, the control algorithm determining which of the plurality of states the backup power supply should be in.
A method for providing uninterrupted power, comprising: monitoring the current of a plurality of capacitors connected in series to each other and being electrically coupled to a power supply and an electrical load; connecting a storage medium to the electrical load when the current in the plurality of capacitors exceeds a predetermined value, the storage medium is adapted to provide a secondary source power in the event of a power interruption in the power supply.
The above described and other features of the present disclosure will be appreciated and understood by those skilled in the art from the following detailed description, drawings, and appended claims.